Quantum networks: where should we be heading?

Quantum key distribution network has become a reality in practical environment. Quantum repeaters have been explored in various physical systems and their combinations. For practical use of them, these new paradigms must be combined with existing or emerging infrastructures of communication and security systems. In this article, we discussed how quantum network can be combined with modern cryptographic technologies in fibre network and with emerging mobile terminals in wireless network, creating new solutions for the future cryptographic and communication systems. Our discussions are summarised in a roadmap.